net.sf.saxon.event

## Class SequenceWriter

- java.lang.Object
- - net.sf.saxon.event.SequenceReceiver
  - - net.sf.saxon.event.SequenceWriter

- All Implemented Interfaces:
    Result, Receiver
  Direct Known Subclasses:
    SequenceExchanger.SequencePusher, SequenceFilter, SequenceOutputter, SequenceTransmitter

      public abstract class SequenceWriter
      extends SequenceReceiver

  This outputter is used when writing a sequence of atomic values and nodes, for example, when xsl:variable is used with content and an "as" attribute. The outputter builds the sequence; the concrete subclass is responsible for deciding what to do with the resulting items.

  This class is not used to build temporary trees. For that, the ComplexContentOutputter is used.

  Author:
    Michael H. Kay

- - ### Field Summary

    - ### Fields inherited from class net.sf.saxon.event.SequenceReceiver

      `pipelineConfiguration, previousAtomic, systemId`

    - ### Fields inherited from interface javax.xml.transform.Result

      `PI_DISABLE_OUTPUT_ESCAPING, PI_ENABLE_OUTPUT_ESCAPING`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `SequenceWriter(PipelineConfiguration pipe)`

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `protected boolean` | `adviseReuse()` Decide whether reuse of the SequenceWriter is advisable
    `void` | `append(Item item, int locationId, int copyNamespaces)` Append an item to the sequence, performing any necessary type-checking and conversion
    `void` | `attribute(NodeName attName, SimpleType typeCode, CharSequence value, int locationId, int properties)` Output an attribute value.
    `void` | `characters(CharSequence s, int locationId, int properties)` Produce text content output.
    `void` | `close()` Close the output
    `void` | `comment(CharSequence comment, int locationId, int properties)` Write a comment.
    `void` | `endDocument()` Notify the end of a document node
    `void` | `endElement()` Output an element end tag.
    `void` | `namespace(NamespaceBinding namespaceBinding, int properties)` Output a namespace declaration.
    `void` | `processingInstruction(String target, CharSequence data, int locationId, int properties)` Write a processing instruction No-op in this implementation
    `void` | `startContent()` The startContent() event is notified after all namespaces and attributes of an element have been notified, and before any child nodes are notified.
    `void` | `startDocument(int properties)` Start of a document node.
    `void` | `startElement(NodeName elemName, SchemaType typeCode, int locationId, int properties)` Output an element start tag.
    `boolean` | `usesTypeAnnotations()` Ask whether this Receiver (or the downstream pipeline) makes any use of the type annotations supplied on element and attribute events
    `abstract void` | `write(Item item)` Abstract method to be supplied by subclasses: output one item in the sequence.

    - ### Methods inherited from class net.sf.saxon.event.SequenceReceiver

      `append, getConfiguration, getNamePool, getPipelineConfiguration, getSystemId, open, setPipelineConfiguration, setSystemId, setUnparsedEntity`

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Constructor Detail

    - #### SequenceWriter

          public SequenceWriter(PipelineConfiguration pipe)

  - ### Method Detail

    - #### write

          public abstract void write(Item item)
                              throws XPathException

      Abstract method to be supplied by subclasses: output one item in the sequence.
      Parameters:
        `item` - the item to be written to the sequence
      Throws:
        `XPathException` - if any failure occurs while writing the item

    - #### startDocument

          public void startDocument(int properties)
                             throws XPathException

      Start of a document node.
      Parameters:
        `properties` - bit-significant integer indicating properties of the document node. The definitions of the bits are in class `ReceiverOptions`
      Throws:
        `XPathException` - if an error occurs

    - #### adviseReuse

          protected boolean adviseReuse()

      Decide whether reuse of the SequenceWriter is advisable
      Returns:
        true if reuse is considered advisable

    - #### endDocument

          public void endDocument()
                           throws XPathException

      Notify the end of a document node
      Throws:
        `XPathException` - if an error occurs

    - #### startElement

          public void startElement(NodeName elemName,
                          SchemaType typeCode,
                          int locationId,
                          int properties)
                            throws XPathException

      Output an element start tag.
      Parameters:
        `elemName` - The element name code - a code held in the Name Pool
        `typeCode` - Integer code identifying the type of this element. Zero identifies the default type, that is xs:anyType
        `properties` - bit-significant flags indicating any special information
        `locationId` - an integer which can be interpreted using a `LocationProvider` to return information such as line number and system ID. If no location information is available, the value zero is supplied.
      Throws:
        `XPathException` - if an error occurs

    - #### endElement

          public void endElement()
                          throws XPathException

      Output an element end tag.
      Throws:
        `XPathException` - if an error occurs

    - #### namespace

          public void namespace(NamespaceBinding namespaceBinding,
                       int properties)
                         throws XPathException

      Output a namespace declaration.
      This is added to a list of pending namespaces for the current start tag. If there is already another declaration of the same prefix, this one is ignored. Note that unlike SAX2 startPrefixMapping(), this call is made AFTER writing the start tag.
      Parameters:
        `namespaceBinding` - The namespace binding
        `properties` - Allows special properties to be passed if required
      Throws:
        `XPathException` - if there is no start tag to write to (created using writeStartTag), or if character content has been written since the start tag was written.

    - #### attribute

          public void attribute(NodeName attName,
                       SimpleType typeCode,
                       CharSequence value,
                       int locationId,
                       int properties)
                         throws XPathException

      Output an attribute value.
      Parameters:
        `attName` - An integer code representing the name of the attribute, as held in the Name Pool
        `typeCode` - Integer code identifying the type annotation of the attribute; zero represents the default type (xs:untypedAtomic)
        `value` - The value of the attribute
        `properties` - Bit significant flags for passing extra information to the serializer, e.g. to disable escaping
        `locationId` - an integer which can be interpreted using a `LocationProvider` to return information such as line number and system ID. If no location information is available, the value zero is supplied.
      Throws:
        `XPathException` - if there is no start tag to write to (created using writeStartTag), or if character content has been written since the start tag was written.

    - #### startContent

          public void startContent()
                            throws XPathException

      The startContent() event is notified after all namespaces and attributes of an element have been notified, and before any child nodes are notified.
      Throws:
        `XPathException` - for any failure

    - #### characters

          public void characters(CharSequence s,
                        int locationId,
                        int properties)
                          throws XPathException

      Produce text content output.
      Parameters:
        `s` - The String to be output
        `properties` - bit-significant flags for extra information, e.g. disable-output-escaping
        `locationId` - an integer which can be interpreted using a `LocationProvider` to return information such as line number and system ID. If no location information is available, the value zero is supplied.
      Throws:
        `XPathException` - for any failure

    - #### comment

          public void comment(CharSequence comment,
                     int locationId,
                     int properties)
                       throws XPathException

      Write a comment.
      Parameters:
        `comment` - The content of the comment
        `locationId` - an integer which can be interpreted using a `LocationProvider` to return information such as line number and system ID. If no location information is available, the value zero is supplied.
        `properties` - Additional information about the comment.
      Throws:
        `XPathException` - if an error occurs

    - #### processingInstruction

          public void processingInstruction(String target,
                                   CharSequence data,
                                   int locationId,
                                   int properties)
                                     throws XPathException

      Write a processing instruction No-op in this implementation
      Parameters:
        `target` - The PI name. This must be a legal name (it will not be checked).
        `data` - The data portion of the processing instruction
        `locationId` - an integer which can be interpreted using a `LocationProvider` to return information such as line number and system ID. If no location information is available, the value zero is supplied.
        `properties` - Additional information about the PI.
      Throws:
        `XPathException` - if an error occurs

    - #### close

          public void close()
                     throws XPathException

      Close the output
      Throws:
        `XPathException` - if an error occurs

    - #### append

          public void append(Item item,
                    int locationId,
                    int copyNamespaces)
                      throws XPathException

      Append an item to the sequence, performing any necessary type-checking and conversion
      Specified by:
        `append` in class `SequenceReceiver`
      Parameters:
        `item` - the item to be appended
        `locationId` - the location of the calling instruction, for diagnostics
        `copyNamespaces` - if the item is an element node, this indicates whether its namespaces need to be copied. Values are `NodeInfo.ALL_NAMESPACES`, `NodeInfo.LOCAL_NAMESPACES`, `NodeInfo.NO_NAMESPACES`
      Throws:
        `XPathException` - if the operation fails

    - #### usesTypeAnnotations

          public boolean usesTypeAnnotations()

      Ask whether this Receiver (or the downstream pipeline) makes any use of the type annotations supplied on element and attribute events
      Returns:
        true if the Receiver makes any use of this information. If false, the caller may supply untyped nodes instead of supplying the type annotation

Copyright (c) 2004-2013 Saxonica Limited. All rights reserved.